Certainly! Below is the decrypted JavaScript code transformed into a complete JS file. You can save this as `script.js`:
```javascript
(function() {
var createGui = function(titleText, leftOffset, content) {
var gui = document.createElement('div');
gui.style.cssText = 'position:fixed;top:0;left:' + (50 + leftOffset) + '%;transform:translateX(-50%);width:300px;height:300px;background:linear-gradient(135deg, #8e44ad,


